Drawing and method of and medium for making the same



Dec; 10, 1940.

w. ISLER DRAWING AND METHOD OF AND MEDIUM FOR MAKING, THE SAME Filed Oct. 26, 1938 Patented Dec. 10, 1940 DRAWING AND METHOD OF AND MEDIUM FOR. MAKING THE SAME William Isler, ,Cleveland, Ohio, assignor to Louis S. I

Sanders, Lakewood, Ohio Application October 26, 1938, Serial No. 237,042

25 Claims. (CI. 41-41) g This invention relates as indicated to drawings suitable for camera copy and the like and to a method of and medium for making the same.

In the preparation of shaded drawings for camera copy, it has heretofore been proposed to use a medium in the form of sheets such as disclosed in Baker Patent No. 1,709,600, bearing an invisible pattern adapted to be chemically' developed to produce shaded effects for line drawings made on such sheets, or sheets such as disclosed in Maier et a1. Patent N0. 1,778,397,

upon which the pattern is directly printed.

In the former case, the process of making the sheets is a rather laborious and expensive one, involving as it does the production on silver print paper of a photographic pattern that may be blanched by the application of a saturated solution of bichioride of mercury and the blanching of such pattern so as to make the same invisible to the eye and of no effect to the camera.

In the latter case, the pattern must likewise be blanched or rendered invisible, and moreover, it is difficult, in printing dots, to avoid a certain degree of fuzziness at the boundaries of the dots, which is due to the fibres being pulled from the sheet by the pressure of the relatively small and sharp projections on the printing plate.

The present invention accordingly has as its primary object the production of a drawing medium in the form of a drawing sheet which can be inexpensively produced, which has an excellent drawing surface, relatively free from the aforesaid condition of fuzziness," and which is admirably adapted for use in making drawings wherein Ben Day and other shaded effects are desired.

To the accomplishment of the foregoing and related ends, said invention then, consists of the steps and means hereinafter fully described and pointed out in the claims, the annexed drawing and the following description setting forth in detail certain means and one mode of carrying out the invention, such disclosed means and mode illustrating, however, but one of various ways in which the principle of the invention may be used.

Fig. 1 is a view of a completed drawing as produced on a medium manufactured in accordance with the invention; Fig. 2 is a fragmentary perspective view, illustrating the first stage in the manufacture of the medium; Fig. 3 is a fragmentary plan view of a shadow dot printing plate which is used in making the medium; Fig. 4 is a view similar to Fig. 2 but showing the shadow dot printing plate, of Fig. 3 in position to transfer the ink thereon to the sensitized sheet of Fig. 2; Fig. 5 is a crosssectional view of the assembled elements shown in Fig. 4; Fig. 6 is a view similar to Fig. 5, but showing the printing plate removed; Fig. 7 is a fragmentary top plan view, on an enlarged scale, of the sheet shown in Fig. 6; Fig. 8 is a view similar to Fig. '7, but showing a development of those portions of the sensitized gelatin surface which are exposed through the shadow dot openings in the ink, and Fig. 9,is a cross-sectional view, taken on the line 9-9 of Fig. 8. v

'Referring more particularly to the drawing, and especially to Fig. 1, I designates .a sheet of paper having a surface on which a line drawing can be produced as in conventional practice, for example the pen lines as indicated at 2. In addition to the line drawing, the drawing has shaded areas or high light effects, as indicated at 3, such effects being produced in the manner now about to be described. v

The sheet I is of ordinary hard-sized white drawing board or paper, to which is applied a thin film 4 of gelatin or other gelatinous material, such as albumen, casein, glue and the like. The sheet is then sensitized" by floating it gelatin side down, for about 15 seconds, in a 20% solution of ammonium molybdate. The term sensitized is here used in a special sense to designate the provision of a film on the sheet bearing a chemical or substance which is initially substantially invisible, but which is capable of beng rendered visible or developed by chemical means. This permits the solution to penetrate only the gelatin film. The excess solution on the surface of the sheet is removed by blotting or by means of rollers'and the sheet permitted todry.

Instead of first applying a film of gelatin and then sensitizing such film, the gelatin or other gelatinous material may be first mixed with the sensitive chemical or substance and then applied to the sheet I, or silver print or similar photographic paper, which is obtainable in the open market, may be used.

A printing plate 5 is-then prepared having a multiplicity of circular openings 6 therein, which are of a size and spaced from each other in a manner similar to the highlight dots of an ordinary Ben Daypositive. Such openings, in actual practice, are extremely small, and very close together, but the size and spacing are greatly enlarged in the present drawing for purposes of clarity.

A film 1 of ink of an opaque character, which is insoluble in the developer to be used for the sensitive film 4 is then applied to the plate 5 in such a manner that the ink covers the entire surface of the plate, with the exception of the openings 6. The film l is furthermore white or substantially in color so as to form a good surface for a line drawing, but such film may be of other colors or shades which can be drawn upon, but which are not sharply contrasting with the film 4. k r

The film I is then transferred directly to the entirese sensitive film 4 of the sheet I, in the manner shown in Figs. 4 and 5, that is, by applyin the plate 5, inked side down, to the film 4 of the sheet. Instead of using a flat printing plate, a-cylindrical or roller type of printing device having openings therein may be used to apply -a film ofink to the film 4.

Theplate 5 is then removed, leaving a sheet, which is the medium of the present invention, and consisting, as shown in Fig. 6, of the sheet I, the sensitive film 4 and an opaque film I, which coats and protects the entire surface of the film 4. with the exception of the small circular dots corresponding to the openings 6 of the plate. In other words, the sensitive surface of the sheet is exposed only through the shadow dot openings in the opaque print.

This medium is then employed by the artist as a drawing surface, on which he may secure any highlight or shading effect he desires by merely applying a suitable developer, as by means of a brush; Where paper, sensitized with a 20% ammonium molybdate solution isused as the drawing medium, a 10% solution of stannous chloride may be employed as a developer.

If the artist desires to produce a shading effest, as at 3 in Fig. 1, he will apply the developer to these portions of the sheet. Only those portions of the film 4, which are exposed through the openings of the film will become visible upon application of the developer, and although the development may progress to portions of the film 4 beyond the boundaries of the openings,

such additionaldeveloped portions of the film will not be visible through the film 1, which, as stated, is opaque.

Since the opaque film 1 is insoluble in the developer, it will, of course, not be affected by the developer. Since molybdenum compounds are immediately reduced by stannous chloride to black molybdenum oxide, the development, in this case, is represented by a reduction of the ammonium molybdate in the film 4 to black molybdenum oxide. The developed dots in Fig. 8 are therefore solid black or substantially black, and these developed dots form the shaded areas 3 (Fig. 1).

After the drawing is completed, it may be used without further treatment for any desired purpose, such, for example, as camera copy for the direct production of line engravings.

Instead of ammonium molybdate and stannous chloride, various other combinations of chemical compounds may be employed to produce the desired color reaction, it being only necessary that the developer and the sensitizer (chemical compound in the gelatin) be colorless or of a light actinic color and the product of the reaction of he two be black, brown, red or a non-actinic color. Among such combinations may be listed the following:

and soluble sulphides In most instances, the chemical compounds in the above combinations are interchangeable, that is to say, the developer can be placed in the gelatin and the sensitizer used as the developing agent or solution.

Instead of using a plate having circular open ings, a plate having square or other-shaped openings may be used, or a plate having slots (for producing line effects) may be used. Moreover, the openings may be irregularly spaced, so as to produce stipple eilects. In fact, any of the patterns or designs ordinarily used in Ben Day workmay be employed.

It is thus seen that I have produced, in an inexpensive 'manner, a drawing sheet which is admirably adaptedfor use in making drawings wherein Ben Day and other shaded effects are desired. Since the areas surrounding the dots are much larger in extent than the dots themselves, the pressure of the printing plate, in applying the opaque coating, is distributed over a greater area, which is continuous, and, as a result, fibres are not broken loose from the sheet..

Consequently, an excellent drawing surface, substantially free from fuzziness, is provided. Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims, or the equivalent of such, be employed.

I therefore particularly point out and distinctly claim as my invention:

1. The method of making a medium for use in preparing drawings suitable for use as camera copy which consists of applying a, coating of a .chemically-developable substance to the 'surface of a sheet, and then applying a coating of an opaque substance insoluble in the developer for said first-named substance to said first-named substance, said lastnamed substance being applied in such a manner as to leave exposed a multiplicity of uniformly spaced dots of said chemically-developable substance. I

3. The method of making a medium for use in preparing drawings suitable for use as camera copy which consists of applying to a sheet hearing a coating of a chemically-developable substance a coating of an opaque substance insoluble in the developer for said first-named subtsance, said last-named coating being applied in such manner as to leave exposed a multiplicity of spaced dots of said chemically-developable substance.

4. The method of making a. medium for use in preparing drawings suitable for use as camera copy which consists of applying to a sheet bearing a coating of a chemically-devel-opable substance a coating of an opaque substance insoluble in the developer for said first-named substance, said last-named coating being applied in such manner as to leave exposed a multiplicity of uniformly spaced dots of said chemically-developable substance.

5. A medium for use in preparing drawings suitable for use as camera copy consisting of 2,224,271 I j J a sheet having a surface bearing a film-oi hpmi cally-developable material and a coating of an suitable for use as camera copy consisting of a sheet having -a surface bearing a film of chemically-developable material and a coating of an opaque material insoluble in thegdeveloper for said first-named material covering said film, with the exception of a multiplicity of spaced dots.

'7. A medium for'use in preparing drawings suitable for use as camera copy consisting 01 a sheet having a surface bearing a film of chemically-developable material anda coating of an opaque material insoluble in the developer for said first-named material covering said film in such a manner as to leave exposed a pattern of spaced dots consisting of said chemically-developa-ble material.

8. The method of preparing a drawing suitable for use as camera copy which consists of applying a developer to selected exposed portions of a medium bearing a film of chemically-developable material, portions of which are exposed through a coating of an opaque substance insoluble in said developer.

9. The method of making a medium for use in preparing drawings suitable for use as camera copy which consists of applying a coating of a chemically-developable substance to the surface of a sheet, and then applying a coating of an opaque substantially white substance insoluble in the developer for said first-named substance to said first-named substance, said last-named substance being applied in such a manner as to leave exposed a multiplicity of spaced dots of said chemically-developable substance.

10. The method of making a medium for use in preparing drawings suitable for use as camera copy which consists of applying to a sheet bearing a coating of a chemically-developable substance a coating of an opaque white substance insoluble in the developer for said first-named substance, said last-named coating being applied in such a manner as to leave exposed a multiplicity of spaced dots of said chemically-developable substance.

11. A medium for use in preparing drawings suitable for use as camera copy consisting of a sheet having a surface bearing a film of chemically-developable material and a coating of an opaque white material insoluble in the developer for said first-named material covering said film in such a manner as to leave exposed a pattern of spaced dots consisting of said chemically-developable material.

12. The method of preparing a drawing suit.- able for use as camera copy which consists of applying a developer to selected exposed portions of a medium bearing a film of chemicallydevelopable material, portions of which are 'exposed through a coating of an opaque white substance insoluble in said developer.

13. The method of making a medium ready to be used in preparing drawings suitable for use as camera copy which consists of applying a coating of a chemically-developable substance to the surface of a sheet, and then applying a coating of an opaque substance insoluble in the developer iorsaid first-named substance to said veloper for said compound, said film= being apposed a multiplicity of spaced dots of said chemi cally-developable substance.

14. A medium ready for use in preparing drawings suitable fol-use as camera copy consisting of a sheet having a surface bearing a film of chemically-developable material and a coating of an opaque material insoluble in the developer for said first-named material covering said film, with the vexception of a multiplicity of spaced areas.

15. The method of preparing a drawing which 10- consists of applying to the surface of a sheet a film containing a chemically-developable material, applying over said film a coating of an opaque substanceinsoluble in the developer for saidmaterial, said coating being applied insuch a manner as to leave exposed a pattern of geometrically-spaced dots consisting of said chemically-developable material, and then developing portions or said pattern.

- 16. The method of preparing a drawing which consists of applying to the surface of a sheet bearing a chemically-developable compound, a film of an opaque material insoluble in the deplied in such a manner as to leave exposed a 25 h'alftone pattern containing said chemically-developable compound, and then developing portions 01' said pattern to form an image.

17. The method of making a medium for use in preparing drawings suitable for use as camera copy which consists of applying a. permanent coating of a chemically-developable substance to visibility bycontact with such developer. 40

18. The method of making a medium for use in preparing drawings suitable for use as camera copy which consists of applying a coating of a chemically-developable substance to the surface of a-sheet, and then applying a permanent coating of an opaque substance impenetrable by the developer for said first-named substance, said last-named substance being applied in such a manner as to leave exposed a multiplicity of spaced areas of said chemically-developable substance, whereby said spaced areas are capable of development and of being brought to visibility by contact with such developer.

19. A medium for use in preparing drawings suitable for use as. camera copy consisting of a sheet having a surface containing a film of chemically-developable material and a permanent coating of an opaque material impenetrable by the developer for said first-named material covering selected portions of said film.

20. A medium for use in preparing drawings suitable for use as camera copy consisting of a sheet having a surface bearing a film of chemically-developable material and a permanent coating of an opaque material impenetrable by the developer for said first-named material coveringsaid film, with the exception of a multiplicity of uniformly spaced dots.

21. The method of preparing a drawing suitable for use as camera copy which consists of apply- 70 ing a developer to selected, uniform sized exposed portions of a medium bearing a film of chemically-developable material, 'said portions being ex-, posed through a coating of an opaque substance impenetrable by said developer, whereby said ex- 75 posed portions are developed to visible areas of given size.

22. A medium for use in preparing drawings suitable for use as camera copy consisting of a sheet having a surface containing a film 01' a material of a color having no photographic value but capable of being chemically developed to a color having a photographic value, and a permanent coating oi an opaque material impenetrable by the developer for said first-named material coveringselected portions 01' said film.

23. A medium for use in preparing drawings suitable for use as camera copy consisting of a sheet having a surface containing a film of a material of a color having no photographic value but capable 01' being chemically developed to a color having a photographic value, and a permanent coating 0! an opaque substance covering said film with the exception of a multiplicity of spaced areas, said substance being impenetrable by the developer for said material.

24. A medium for use in preparing drawings suitable for use as camera copy consisting of a sheet having a surface containing a continuous film oi chemically-developabie material and a coating oi an opaque material impenetrable by the developer for said first-named material covering selected portions of said film.

25. A medium tor use in preparing drawings suitable for use as camera copy consisting of a sheet having a surface containing a continuous film of a chemically-developable material and a coating of an opaque substance covering said film with the exception of a multiplicity of spaced areas. said substance being impenetrable by the developer for said material.

WILLIAM ISLER. 

